Sears and roebuck chassis 101.614 restoration

[Vectorgw]

I'm at the end of restoring this old am radio. replaced all caps, most of the tubes. The only problem I'm having for the most part is trying to align the broadcast band. I get it all except when it wants me to tune to 600 and adjust c18 the padder I cat get a signal at 600kc it does however have a signal just above 700 kc with the generator set to 600kc. Ive double checked wiring, etc. Any thoughts would be appreciated..

Thank you

 

[gadget73]

does the dial pointer track properly? Usually all the way down you have tot get the pointer to land at the bottom of the scale. if the pointer has been slid, it will not adjust correctly.

if thats good, did you replace the small value caps around the tuner? If so, its probably way off. You may have to mess with both the top and bottom adjustments back and forth to get it right. With a lot of that stuff even just physically moving the parts right around the tuner can throw it off.

 

[larryderouin]

+1 what gadget said. If it has a logging scale (0 to 100) make sure the pointer hits 0 (ZER0) when the tuner is run all the way down to the low end of the scale. If it doesn't then you need to reset it to the bottom of the frequency scale, then adjust the front end to 600kc on the low end and usually 1400kc on the upper end. If you have a strong station at 600 to 610 zero beat it as close as you can, and adjust the low end for that station. Do the same for the upper end (1380kc to 1420kc). Go back and forth a few times until the adjustments are so small as to not even be needed. I have a very strong station @ 600kc which washes out my generator, and another 2 at 1370 and 1430, so my generator only gets used to set the 455kc or whatever frequency the manufacturer has set as the primary freq. It works really well on most radios, and AM/FM sets from the 70's. Sansui used to set the AM primary in a range from 425 to 480kc and said to NOT adjust to 455KC as the frequency was somewhere in the range of 425 to 480kc and it had to be determined. WHAT A PITA!

 

[gadget73]

broadcast stations are usually going to be more accurate and more stable than the typical RF generator anyway. Also rather less annoying to listen to than a steady tone.

 

[drtool]

[QUOTE="gadget73, broadcast stations are usually going to be more accurate and more stable than the typical RF generator anyway. Also rather less annoying to listen to than a steady tone.[/QUOTE]............. I see you have not listened to radio lately.

 

[gadget73]

lol, ok I take your point. I was mostly meaning that it doesn't make my ears ring like a steady test tone does. The actual content can be rather terrible at times. The AM band especially is prone to fairly awful stuff, basically sports, Jesus, or talking head conspiracy nuts. There is one station playing what sounds like a Mexican restaurant soundtrack, and honestly I think its the only thing worth listening to.

 

[larryderouin]

AAHHHH! Mariachi "R" us..... LOL! I heard that soundtrack at the Mexican restaurant around the corner last week. It wasn't too bad either. B, S, and T meets the T.J.B.